1. Field of the Invention
The invention is particularly, but not exclusively, concerned with a manufacturing process and apparatus involving the molding of a shell of confectionery material. The molded shell may, or may not, be subsequently filled with other material, usually confectionery material and that subsequent filling step may be included within the broadest scope of one of the aspects of the invention.
This manufacturing process will be referred to hereinafter as "shell molding", and, is so known by those skilled in this Art.
For the purposes of this specification the term "confectionery material" when used herein refers to any edible foodstuff which contains sugar and/or artificial sweetening material.
2. Description of the Prior Art
There are a number of problems and deficiencies associated with the current process for shell molding of material, and, in one particular instance, when the material to be molded is confectionery.
When the material to be molded is confectionery, it is very difficult, if not practically impossible, to predetermine the wall thickness, or thicknesses if a variety of wall thicknesses are desired, of the molded confectionery article and produce an article having that predetermined thickness or those thicknesses, using currently known processes. This is so, even with the simplest of shapes. For more complex shapes the difficulties in producing a shell of material having controlled wall thickness, and such articles represent acceptable and economically desirable articles, increase greatly,
Accordingly, it is not currently possible to keep wall thicknesses in a shell molded article relatively thin and uniform in the case of simple shapes, that is, as thin as the inherent properties of the material would allow, or, to produce articles having controlled wall thicknesses in predetermined areas of the article, as may be desirable in the case of articles having complex shapes.
However, it is desirable for some simple shapes, to be able to control and predetermine the wall thickness when shell molding an article, and, it is of great benefit if the wall thickness of the article can be made uniform throughout. For other articles it is desirable to be able to control and predetermine the wall thickness so that, for example, additional strength can be provided to one or more parts of the article by the provision of a thicker wall in that area or areas.
Also, when considering the problems associated with molding more complex shapes generally, there is often a problem with "backlocking" of the article in the mold, which is caused by one or more protrusions of such an article not being able to freely move past other portions of the mold, and thus "locking" the article in the mold.
Also, as will be appreciated by those skilled in the molding art, there are many instances where effective demolding of an article to release it from a mold requires that the material from which the article is molded contracts slightly when it solidifies. However, there are some occasions when the molding material is such that there is no contraction, or virtually no contraction, of the material on solidification. In such cases acceptable demolding of an article from a solid mold is extremely difficult, or impossible.
It is also possible that difficulties may be encountered when filling a shell-molded article with other material, if the addition of that other material causes the filled article to remain in the mold, under normal mold release action, that is, the shell of material sticks to the mold after the filling step. This could occur where the filling step alters the characteristics of the shell-molded material and that alteration relates to the mold release capabilities of the material. It is also possible that the nature of the filling material may require a shell-molded material of less favourable mold release character to be used, as indicated in the preceding paragraph.
It is an object of the present invention to provide a process and apparatus for the manufacture of a shell molded article, in which the wall thickness achieved, in at least a substantial part of the article, is able to be predetermined.
It is also an object of the present invention to provide a process and apparatus for the manufacture of a molded article, in which the article may be readily removed from the mold, due to removal of a substantial portion of the mold surfaces from said article, prior to removal.